Circuit breaker control system



Sept 7, 1943- M. E. REAGAN Erm.

CIRCUIT BREAKER CONTROL SYSTEM Filed Dec. 16, 1941 l INVENTOR 5 y Maur/'ce E 760900 and Guy M C72 amp/2e Patented Sept. 7, 1943 2,329,081 CIRCUITBREAKER/ CONTROL SYSTEM Maurice E. Reagan and Guy W. Cliampney,

Pittsburgh, Pa.,

assignors Electric c Manufacturing Company,

to Westinghouse East Pittsburgh, Pa., a corporation of Pennsylvania Application December' 16, 1941, Serial No. 423,19()

(Cl. l75--294) 7 Claims.

Our invention relates, generally, to circuit breaker control systems, and, more particularly, to control systems embodying antipumping means and means for positively closing and latching circuit breakers.

In previously kno-wn circuit breaker closing systems in which a plurality of relays have been employed to close a circuit breaker andr have been interconnected to prevent pumping ci the breakn er, it has been found that the relay system often releases before the circuit breaker latches in closed position, thus resulting in failure of the circuit breaker to positively close and latch.

It is an object of` our invention to provide a circuit breaker control system which shall function to so control a circuit breaker as to positively close and latch the breaker, and which shall be simple and efficient in operation and inexn pensive to manufacture, install, operate, and maintain.

These and other objects and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawing, in which like reference characters indicate like parts the several ngures, and in which,

Figures 1, 2, and 3' are each a diagrammatic view of a circuit breaker control system embodying the principal features of the invention.

In practicing the invention, in the embodiment of Fig. 1, a circuit breaker d having a trip-free operating mechanism including a closing coil 6 and a trip coil 8 is shown. A relay I0 controls the closing coil 6 and is, in turn, controlled by a relay l2 and a close circuit control device it. The relay i2 is held energized in a circuit which includes a reactor i8 which is rendered operative to slowly decrease the energization of the relay i2 when the circuit breaker closes to thereby continue the energization of the relay iii and the closing coil il for an interval after the breaker has closed, thereby insuring that the breaker will be positively closed and latch/ed before release of the closing coil 6.

The embodiment of the invention. shown in Fig. 2 is a circuit breaker control system such as may be employed at automatic stations and includes a master relay 2u through which the relays ii) and l2, the reactor i8, and the closing and trip coils 6 and 8 function in a manner similar to the systern of Fig. l.

The system oi Fig. 3 is an automatic reclosing system embodying the principles of the closing elements of the systems of Figsl and 2, and in* form of a recloser for preventing the breaker Il from closing in the event that it trips within a predetermined time after any closure.

Considering the invention more in detail with reference to Fig. 1, the circuit breaker l may be disposed to connect a power bus, represented by the conductors 24 and 26, with a distribution line including conductors 28 and 3%. A source of alternating current control power, represented by the conductors 32 and 34, may be provided.

The closing-coil of the circuit breaker l op erates against the bias of a spring member E5 and through engaging detents 38 and 4G to move the linkage 42 against the bias of a spring member 55 to close the circuit breaker. When the circuit breaker is in closed position, detent G on an arm 50 which actuates the linkage 42 will be engaged by a spring-pressed detent 5S to hold the circuit breaker in closed circuit position. The trip coil of the circuit breaker when energized will function to move the arm 5G downwardly to disengage the detent i6 from the detent 48 and permit the spring member Gli to actuate the linkage 42 to move the circuit breaker to open circuit position.

An energizing circuit is provided for the relay l0 extending from the conductor 3i through conductors 52 and 54, the winding of the relay I0, a conductor 56, a contact element E8 of the relay I2, a conductor 69, the contact element of the close circuit control device l'l, and the conductors 62 and Sito conductor 32. The relay i@ controls an energizing circuit for the closing coil 6 of the circuit breaker d extending from the conductor 32 through conductors 5S and S8, a

Contact element 'i0 of the relay i6, a conducto-r l2, a rectifier 'llLfconductors 'i6 and 78 extending between the rectifier 'I4 and and the closing coilt, and conductor 8D to the conductor Sii.

An energizing circuit for the relay i2 extends from the conductor 32 through conductors G6 and 82, the contact element of the circuit control device i4, a conductor 34, the Acontact element ci trip circuit control device Bt, conductors 88 and 9E, the winding of the relay l2, and the conductor 52 to the conductor 3. The relay i2 controls its own holding circuit through its contact element Q2 which circuit extends from the conductor 32 through the conductor E6, the Contact element conductors 94 and 96, a Winding S8 of the reactor i8, a conductor ME, another winding m2 ci the reactor I8, the conductor Si?, the winding oi' the relay l2 and the conductor 52 to the conductor 34.

Another winding L94 of the reactor i3 is enerized direct current power in a circuit which i5 from the conductor 32 through the con- .uc.cr 06, thc contact element 82, the conductor 4, a rectifier |00. a conductor |63, the winding conductors H and I||, a resistor I|2, and a conductor H4 to the conductor 34. A shunting circuit is provided for the reactor winding |04 which extends from one terminal of the Winding |64, through conductors |08 and IIE, the contact clement I6, and conductor |I0 to the other terminal of the Winding |04.

The windings S8, |32 and |04 of the reactor I8 are disposed as indicated on a common core IIB. The direct current energization of the Winding |04 is such that this Winding saturates the core H8 and thereby minimizes the impedance of the windings 03 and |32 which are connected in the holding circuit of the relay I2 to thereby insure full energization of the Winding of the relay i2. When the closing coil 6 of the circuit breaker moves the contact element I6 to closed circuit position, the shunting circuit for the Winding |04 will be closed and Will cause the direct magnetizing current flowing in the coil |04 to he reduced to practically zero. The collapse of the direct current nur. in the core I I8 will require an interval of time, and when it is conipleted the reactance of the windings 93 and |02 Will be so increased as to prevent suilicient current to flow in the Winding of the relay I2 to maintain it actuated through its holding circuit.

An energizing circuit for the trip coil B of the circuit breaker 4 extends from the conductor 32 through the conductors 64 and 62, the contact element of the circuit control device 86, in actuated position, conductors and |22, the winding of the trip coil 8, a conductor |24, a contact element actuated by the circuit breaker 4, and a conductor |26 to the conductor 34. Another energizing circuit for the trip coil 8 is controlled by a potential responsive relay |21, and extends from the conductor 32 through a conductor |23, a contact element of the relay |21, the conductor |22, the Winding of the trip coil 8, the conducto-r |24, the contact element |25, and the conductor |25 to the conductor 34.

In the operation of the embodiment of the invention of l, when it is desired to close the circuit breaker 4, the close circuit control device I4 may be manually actuated to close the energizing circuit for the relay ID. The actuation of the relay I0 will close the energizing circuit for the closing coil 6 which will close the circuit breaker 4 and move the Contact element I6 to circuit closing position. The closing of the shunting circuit for the reactor Winding |04 will gra-dually increase the impedance of the holding circuit of relay I2 and cause the relay I2 to release after an interval of time. When the relay I2 has release turn, deenergiz'e the closing coil Ii'. Thus the energization ci' the closing coil 6 will be maintained for an interval of time after it has closed the circuit breaker to thereby insure that the circuit breaker willv be fully and positively closed, and that the detent 43 has ample time to enga-ge the detent 48 to hold the circuit breaker in closed position.

The circuit breaker 4 is prevented from pumping when the circuit control device I4 is held actuated by the fact that the original energizing cir yuit for the relay I2 extends through the contact element of the circuit control device I4 in released position. Therefore, it is necessary that the relay I0 will he released and will, in i CTl control device I4 be released before there is another closure of the circuit breaker 4.

In the embodiment of the invention of Fig. 2, the energizing circuit for the relay I0 extends the conductor 34 through the conductors 32, |34, and |35, the winding of the relay |0, a conductor |30, a contact element |38 of the relay l2, a conductor |40, a contact element |42 ofthe relay 20, and conductors |44 and |46 to the conductor 32.

The contact element 'I0 of the relay I0 controls an energizing circuit for the closing coil 6 extending from the conductor 34 through the conductors |32 and |34, the Contact element '|0, the conductor l2, the rectifier' |4, the conductors IG and T8 which extend between the rectier 'I4 and the winding cf the closing coil 6, and a. ccnducwr 80 to the conductor 32.

The energizing circuit for the relay I2 extends from the conductor 32 through the conductors |46 and |48, a contact element |50 of the relay 20, conductors |52 and |54, the Winding of the rela-y I2, and the conductor |32 to the conductor 34. A holdingr circuit for the relay I2 extends from the conductor 32 through the conductor |46, a Contact element |56 of the relay |2, ccnductors and |60, reactor Winding 9B, the conductor |23, reactor Winding |02, the conductor '54, the Winding of the relay I2, and the conductor |32, to the conductor 34. The reactor |8 is a substantial duplicate ci that described in connect-ion with the system of Fig. l, and has like reference characters applied to corresponding elements. The shunting circuit for the direct current winding |04 of the reactor i8 is controlied by contact element I6, and described hereinbefore in connection with the system of Fig, l.

An energizing circuit is provided for the relay 20 and extends from ihe conductor 34 through a conductor |62, a close circuit control device |64, a conductor |36, a contact element |68 of a voltage responsive relay |69, conductors |80, |82 and |84, the Winding oi the relay 20, a conductor |36, a resistor |88, a conductor |50, a contact element |02 and a conductor |54 to the conductor 32. A holding circuit for the relay 20 extends from the conductor 34 through conductors |32 and |55, a Contact element |98 of the relay 20, the conductor |84, the Winding of the relay 23, the conductor |35, the resistor |88, the conductor |90, the contact element |92, and the conductor |94 to the conductor 32.

The relay 20 may be released by o. shunting circuit controlled by a back contact element 200 of the voltage responsive relay |69 which extends from one terminal of the winding of the relay 20 through conductors |84, |82 and |89, the contact element 200, and conductors 202 and |06 to the other terminal of the winding of the relay 20, A shunting circuit for releasing the relay 20 is also controlled by a trip contact elcment 204 and extends from one terminal of the winding of the relay 20 through the conductors |84 and |32, the contact element 204, and conductors 202 and |86 to the other terminal of the Winding of the relay 20.

The close contact element |04 and the trip" contact element 204 may be contact elements controlled by a remote control system from a control station over which the apparatus inoludinsr the circuit breaker 4 disposed at a remote station is controlled and/or supervised.

A relay 206 is connected to be controlled by a contact element 208 in a circuit extending from the conductor 34 through a conductor 2I3, the contact element 268, a conductor 2I2, the wind-- ing of the relay 266, conductors 2I4 and |33, the contact element |32 and the conductor |94 to the conductor 32. The relay 266 is disposed to actuate a detent 2|6 against the bias of a spring member 2I8 from engagement with a detent 226 to permit the contact element |32 to drop to open circuit position to thereby break the energizing and holding circuits for the relay 20. The contact element 268 may be actuated by any device at the station at which the circuit breaker 4 is installed, responsive to a condition such that it is undesirable that the circuit breaker 4 be again closed until after inspection of the equipment controlled by the circuit breaker 4. The con tact element |92 will remain in open circuit position until manual actuation of the member 22| moves it to closed circuit position where the detent 2I6 will cooperate with the detent 226 to hold the contact element |32 in closed circuit position.

In the operation of the system of Fig. 2, when it is desired to close the circuit breaker the contact element |64 may be actuated to close an i coil 6 at which time the reactor Winding |34 will 1;;

be shunted and the impedance of the reactor windings 93 and |62 will so increase after a time interval as to cause the relay I2 to be released. The release of the relay I2 will open the energizing circuit for the relay i6 which, in turn, will deenergize the closing coil E, after a sufcient time interval to permit the breaker to be fully and positively closed and to permit the detent 48 to positively engage the detent 46 to hold the circuit breaker 4 in closed circuit position.

In the embodiment of the invention of Fig. 3, the relay I3 has an energizing circuit which eX- tends from the conductor 34, conductors |32, |34, and |35, the Winding or" the relay III, a con ductor 222, a contact element 224, which is f mounted upon an arm 225 and biased to the position to which it is actuated by circuit control devices 226 and 221 by a spring member 228, a conductor'Za, a contact element 232 of the relay I2 and conductors 234 and 236 to the conductor .f'

232. The relay I6 controls an energizing circuit for the closing coil 6 which extends from the conductor 34 through the conductors |32 and I 34, the contact element 16 of the relay Iii, the conductor the rectier 14, the conductors 16 and 18 which extend between the rectier 14 and the closing coil 6, and the conductor 82 to they conductor 32.

An energizing circuit for the relay I2 extends from the conductor 32 through conductors 238, 240 and 24|, a contact element 242, conductor 244, a contact element 246 which is actuated by the circuit breaker 4 in open circuit position, a conductor 248, aconductor 250, the winding of: the relay I2 and the conductor |32 to the conductor 34. The circuit control device 226, when actuated, also closes an energizing circuit for the relay I2 which extends from the conductor 32, through conductors 252 and 254, a contacteiement of the circuit control device 226, conductors 248 and 250, the winding of the relay I2 and the conductor |32 Vtothe conductor 34. A holding circuit for the relay I2 extends from the conductor 32, through the conductor 236, a contact element 256 ofthe relay I2, a conductor 258, the reactor winding 38, the conductor I 66, the reactor winding 02, the conductor 250, the winding of the relay I2 and the conductor |32 to the conductor 34.

The direct current winding |04 of the reactor I8 is energized in a circuit which extends from the conductor 34 through conductors 266, 262, and 264, the rectifier |06, a conductor 256, the direct current reactor Winding |64, a conductor 268, a resistor 210 and conductors 212 and 236 to the conductor 232. A shunting circuit for the direct current reactor winding |64 is controlled by the contact element I6 and extends from one terminal of the winding I 32 through the conductors 266 and 214, 'the Contact element |6 and conductors 216 and 263 to the other terminal of the Winding |64.

An energizing circuit for the trip coil 8 extends from the conductor 32 through the conductors 252 and 254, the contact element of the circuit control device 221, conductors 218 and 233, the winding of the trip coil 8, a conducto-r 232, a con tact element 284 actuated by the circuit breaker 4 in closed circuit position, and conductors 26:2 and 263 to the conductor 32. An overload or any other suitable type of protective relay 286 also controls an energizing circuit for the trip coil 8 which extends from the conductor 32 through the conductor 288, a Contact element 236 of the relay 286, the conductors 218 and 33, the winding of the trip coil 8, the conductor 282, the Contact element 284 and conductors 262 and 266 to the conductor 34. i

The timing device or recloser 22 comprises a timing element 232 which is connected in a circuit controlled by a contact element 294 and the contact element 246 in front contact positionk extending from the conductor .2 through the conductor 238, the contact element 294, a conductor 296, the timing element 292, a conductor 283, the

Contact element 246 and the conductor 260 to the conductor 34. The timing element 232 moves a contact member 336 to circuit closing position after a predetermined interval of energization.

The contact elements 242 and 292 are disposed to be moved into the right-hand position in which they are shown in the drawing by a coil 332 and to a left-hand position by a coil 324, and are adapted to remain in the positions to which they are moved by the coils 302 and 364. The coil 364 is controlled by the contact element 'i2 of the relay I0 in a circuit which extends from the conductor 34, through the conductors |32 and |34, the contact element 10, conductors 12 and the coil 364, and conductors 24U 233 to the conductor 32. The coil 362 is connected to be energized in a circuit which extends from the conthe contact element 242 in the leftdiand position.

,- a conductor 323, the coil 332, a conductor 3Iil,

the contact element 300, a conductor SI2, a con tact element 3I4 actuated by the circuit breaker 4, and conductors 262 and 253 to the conductor In the operation of the embodiment of the invention of Fig. 3, the circuit control device 226 may be actuated. If the relay I2 is not energized in the circuit controlled by the contact ele ment 242, the circuit control device 226 will close an energizing circuit for the relay I2 and the contact element 232 of the relay I2 and thc contact element 224 actuated by the circuit control device 226 will close an energizing circuit for the relay IIJ. The actuation of the relay III will close the energizing circuit for the closing coil 6 which will cause a circuit breaker 4 to be closed. The contact element I6 actuated by the closing coil S will close the sliunting circuit for the direct current reactor winding I 94 which will gradually increase the impedance of the holding circuit for the relay I2 and cause the relay I2 to be released after a short interval of time. The relay I0 and the closing coil 6 will be released upon the release of the relay IZ a sufficient interval after the closure of the relay 4 to insure positive closure of the circuit breaker and positive latching of the circuit breaker in closed position by the dctents 46 and 48.

The actuation of the relay IS causes the coil 304 to be energized to move the contacts 242 and 294 to the lefthand circuit closing position. The contact elements 294 and 246 will cause the timing element 292 to be energized, and, after a time interval determined by the adjustment of the timing element 292, the co-ntact member 3&9 Will be actuated to circuit closing position to energize the coil 362 which will move the Contact elements 242 and 294 to the riehthand position shown in the drawing.

Should an overload or any other fault on the load conductors 29 and 35) cause the relay 286 to trip the circuit breaker 4, the energizing circuit for the relay I2 will be completed by the contact element 246 in back contact position to immediately actuate the relay I2, whose contact element 232 will close the energizing circuit for the relay IS. The actuation of the relay IU will close the energizing circuits for the closing coil 6 and the coil 334, and the circuit breaker will be reclosed immediately. With the contact elenient 242 in the left-hand position to which it has been moved by the coil 304, the energizing circuit for the relay I2 cannot again be energized until the timing element 292 has caused the coil S02 to return the contact element 242 to the right-hand circuit closing position. Thus, should the circuit breaker again trip immediately after any closure, it will be held open by the failure of the relay I2 to pick up and cause the relay I2 to energize the closing coil 6.

When the circuit breaker 4 is opened by the actuation of the circuit control device 221, the Contact element 224 will be moved to open circuit position and held in that position by the spring member 228, thus preventing reclosure of the circuit breaker 4 until the circuit control device 223 is also actuated.

It is to bc understood that the relays |21 and 69 of Figs. l and 2 respectively are merely illustrative of one type of protective relay and that protective relays such as the fault relay 286 of Fig. 3 may be employed instead of or in addition to the relays I2I and |69 to perform the functions of controlling the circuits controlled by the relays I2'I and |59.

Thus it will be seen that We have provided a circuit breaker control system which shall iunction to so control a circuit breaker as to positively close and latch the breaker, and which shall be simple and efficient in operation and inexpensive to manufacture, install, operate and maintain.

In compliance with the requirements of the patent statutes, we have shown and described herein the preferred embodiments of our inven- Iii tion. It is to be understood, however, that the invention is not limited to the precise constructions shown and described, but is capable of modification by one skilled in the art, the embodiments herein shown being merely illustrative of the principles of our invention.

We claim as our invention:

l. In a circuit breaker control system, a first relay for energizing the closing means of the circuit breaker, a second relay for energizing the rst relay, and means responsive to the closing of the breaker for releasing the second relay comprising a reactor connected in circuit with the Winding of the second relay, a saturating means for the reactor and means responsive to the closure ol the breaker for rendering the saturating means inoperative.

2. In a circuit breaker control system, a first rela-y, an energizing circuit for the closing means of the circuit breaker including a front contact element of the first relay, a second relay, an energizing circuit for the iirst relay including a front contact element of the second relay, a reactor havin-g a iirst and a second winding, means for so energizing the iirst reactor Winding as to saturate the reactor core, an energizing circuit for the second relay including the second reactor winding, and means responsive to the closure of the breaker for deencrgizing the iirst reactor winding.

3. In a circuit breaker control system, a rst relay, an energizing circuit for the closing means of the circuit breaker including a contact clement of the first relay, a second relay, an energizing circuit for the first relay including a contact element of the second relay, a reactor having a iirst and a second winding, means for so energizing the first reactor Winding with direct current as to saturate the reactor core, an alternating current energizing circuit for the second relay including the second reactor Winding, and circuit means responsive to the operation of the closing mechanism of the breaker for shunting and thereby decreasing the energization of, the

'i first reactor winding,

4. In a circuit breaker control system, a first relay connected to energize the closing means of the circuit breaker, a circuit control device, a second relay, an energizing circuit for the first relay including a front contact element of the circuit control device and a contact element of the Second relay, a reactor having a first and a second Winding, means for so energizing the first reactor winding with direct current as to saturate the reactor core, a iirst alternating current energizing winding for the second relay including the second reactor winding, a contact element of the second relay and second reactor winding, a second energizing winding for the second relay including a back contact element of the circuit control device, and means responsive to the actuation of the circuit breaker closing means for decreasing the energization of the first reactor winding sufiiciently to cause the release of the second relay.

5. In a circuit breaker control system, a. first relay for energizing the circuit breaker closing means, a second relay, and a third relay, an energizing circuit for the rst relay including contact elements of the second and third relays, an energizing circuit and a holding circuit for the third relay, a first energizing circuit for the second relay including a back contact element of the third relay, a reactor having a rst and a second winding, means for so energizing the rst reactor winding as to saturate the reactor core, a second alternating current energizing circuit for the second relay including the second reactor winding and a contact element of the second relay, and means responsive to the actuation of the circuit breaker closing means for de creasing the energization of the rst reactor winding suiiiciently to release the second relay.

6. In a circuit breaker control system, a rst relay, a second relay, a third relay, circuit means whereby actuation of the rst relay causes the circuit breaker closing means to operate, an energizing circuit for the first relay including a contact element of the second relay, an energiizng circuit for the third relay including a control element of the first relay, a first energizing circuit for the second relay including a back contact element operated by the circuit breaker and a Contact element actuable to open circuit position by the third relay, a reactor having a rst and a second winding, means for so energizing the rst reactor Winding with direct current as to saturate the reactor core, a second energizingr circuit for the second relay including a contact element of the second relay and the second reactor Winding, and means responsive to the actuation of the circuit breaker closing means for decreasing the energization of the first reactor winding sufciently to release the second relay.

7. In a circuit breaker control system, a first relay, a second relay, a third relay, circuit means whereby actuation of the rst relay causes the circuit breaker closing means to operate, an energizing circuit for the first relay including a contact element of the second relay, an energizing circuit for the third relay including a contact element of the iirst relay, a rst energizing circuit for the second relay including a back contact element operated by the circuit breaker and a contact element actuable to open circuit position by the third relay, a reactor having a first and a second winding, means for so energizing the first reactor Winding with direct current to saturate the reactor core, a second energizing circuit for the second relay including a Contact element of the second relay and the second reactor Winding, means responsive to the actuation of the circuit breaker closing means for decreasing the energization of the iirst reactor winding suiiciently to release the second relay, and time delay means responsive to the actuation of the third relay and the closure of the circuit breaker for reclosing the contact element actuated by the third relay a predetermined time after the closure of the circuit breaker.

MAURICE E. REAGAN. GUY W. CHAMPNEY. 

